An epidemic of dental disease afflicts the United States. Twenty-nine percent of Americans have untreated caries. Methods to prevent this disease are well understood. Application of these methods presents a challenge to the public health system. Most ongoing public health efforts address the problem at one of three points: (1) use of fluoride to remineralize teeth for better resistance to decay (2) protection of cariogenic pits and fissures with dental sealants or (3) making more professional dental care available to underserved populations. Neglected by all three tactics is the individual's responsibility for his or her own oral health. Habits of nutrition and especially of oral hygiene are critical to maintenance of oral health throughout life. However these require education and motivation at an early age. It is difficult for public health systems to improve individual behavior. A new tool may have the potential to change this. Videogames can develop skills, promote cognitive learning and build motivation. New input devices (notably the WiiMote(R)) permit the monitoring of free-range real-world motion. Using such a device, a game can closely monitor player performance of toothbrushing action and adaptively provide appropriate instruction, correction and reinforcement. For example: games of the popular "rhythm-match" genre score the player's performance of specific physical movements with precise timing. By replacing the guitar with a toothbrush, the game could employ these mechanisms to promote mastery of manual brushing skills and pacing. Can a game be developed which exploits this potential and improves the oral hygiene habits of children? A carefully-designed study aims to answer that question. A positive result will point toward a tool for improved dental health. Meanwhile more is learned about the potential of videogames to promote healthy behavior. PUBLIC HEALTH RELEVANCE: One American in four has tooth decay and many have little hope to ever see a dentist. This misery can be prevented with a toothbrush - if good skills and motivation are taught. Some parents do not teach these. Can children learn them from a videogame?